This invention relates to the environmental protection for a camera. The use of a conventional camera in rain, dust, water splashing or the like is not preferable. This may spoil the film or may break down the camera. Thus, the operation of the conventional camera is limited to a certain extent. Conventional interchangeable view finders for cameras can be roughly divided into an interchangeable view finder of pull-up type as shown in FIG. 1 and an interchangeable view finder of drawing type as shown in FIG. 2.
FIG. 1 shows the interchangeable view finder of pull-up type. This interchangeable finder can be installed on the camera body by depressing it downward in one direction of the arrow and by pulling it upward in the opposite direction of the arrow. The pull-up type interchangeable finder 1 can be mounted on the camera body by depressing the interchangeable finder 1 until it engages the locking member (not shown) of the camera body 2. In some of the cameras of this type, a rubber cover 3 as shown in FIG. 1, abuts against the camera body 2 by the utilization of the elasticity or bending characteristic of the rubber cover 3. This cover is secured to the pull-up type interchangeable finder 1 to prevent the entry of dust through the gap between the pull-up type interchangeable finder and the camera body. However, this method is insufficient when the camera is used under adverse weather conditions such as in rain or in marine use where water splashing is common.
FIG. 2 shows the interchangeable view finder of drawing type. In this finder interchanging system, the rails (or protruded parts) of the drawing type interchangeable finder are engaged with rail grooves 5 secured to the camera body 2. That is, the interchangeable finder 4 can be installed on the camera body 2 by pushing the interchangeable finder 4 in one direction of the arrow and removed therefrom by pushing the interchangeable finder 4 in the opposite direction of the arrow. In the camera of this type, the interchangeable finder 4 slides on the camera body when the interchangeable finder 4 is mounted on the camera body or removed therefrom. Accordingly, it is not preferable to interpose a viscoelastic member such as rubber high in coefficient of friction between the interchangeable finder 4 and the camera body because the viscoelastic member will obviously make it difficult to remove the finder. Thus, in such systems sealant has not been provided between the interchangeable finder 4 and the camera body.